Authors:Shi Jingyan, Wang Zhiyong, Liu Yuwen, and Wang Cunxin
medicine and quality monitoring, was reported rarely. Though several literatures have reported the thermalbehavior of enoxacin [ 4 – 6 ] and its metal complexes [ 7 ], due to adopting only thermal analysis technique and the single heating rate method, it
The thermal behaviour of the complexes of N,N-diethyl-N′-benzoylthiourea (DEBT) with Ni(II), Cu(II), Pt(II), Pd(II) and Ru(III) was studied using differential thermal analysis (DTA) and thermogravimetry (TG). These complexes undergo only a pyrolytic decomposition process. A gas chromatography-mass spectrometry combined system was used for the verification of the first decomposition product and X-ray diffraction method for the characterization of the final products of pyrolysis.
Authors:J. Locatelli, E. Rodrigues, A. Siqueira, E. Ionashiro, G. Bannach, and M. Ionashiro
Solid-state Ln(Bz)3·H2O compounds where Ln stands for trivalent yttrium or lanthanides and Bz is benzoate have been synthesized. Simultaneous thermogravimetry-differential
thermal analysis (TG-DTA), X-ray powder diffractometry, infrared spectroscopy and chemical analysis were used to characterize
and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration,
thermal stability and thermal decomposition of the isolated compounds.
thermo-infrared spectroscopy analysis. Based on these analyses, the kaolinite–DMSO intercalation complex of a low defect (well crystallized) kaolinite from Zhangjiakou in China was prepared. The thermalbehavior of the complex heated in different
size of hematite has a strong effect on the thermalbehavior of rutile and anatase-doped hematite ceramic systems, and the additions of rutile and anatase suppressed the crystallization of hematite [ 20 , 21 ]. The hematite with smaller particle sizes
Authors:Rodica Olar, Michaela Badea, E. Cristurean, C. Parnau, and D. Marinescu
The complexes of the type M(HDMBG)2(CH3COO)2nH2O ((1)
M:Mn, n=1.5; (2)
M:Ni, n=0; (3)
M:Cu, n=2; (4)
M:Zn, n=2; DMBG: N,N-dimethylbiguanide)
present in vitro antimicrobial activity. The thermal analysis has evidenced
the thermal intervals of stability and also the thermodynamics effects that
accompany them. The different nature of the ligands generates a different
thermal behaviour for the complexes. The thermal transformations are complex
processes according to TG and DTG curves including dehydration, oxidative
condensation of –C=N– units as well as thermolysis processes.
The final products of decomposition are the most stable metal oxides.
Authors:R. Macêdo, J. Barbosa-Filho, E. da Costa, and A. de Souza
The terpenoids acetyl sitosterol, lupeol, acetyl diosgenin and stigmasterol were studied. Comparison of the thermogravimetric
curves and the activation energies of the terpenoids suggested the following sequence of thermal stability: acetyl sitosterol
< acetyl diosgenin < lupeol < stigmasterol. The DSC curves allowed determination of the melting points and the degrees of
purity. Comparison of the TG and DSC curves revealed the presence of phase transitions without mass loss that were attributed
to rearrangements in the terpenoid molecules.
Authors:C. Ribeiro, M. Crespi, L. Guinesi, C. Guerreiro, and H. Zorel
Tin(II) complexes with 8-hydroxyquinolinate in solid state have been obtained by adding aqueous ammonium to a solution containing
stannous chloride and 8-hydroxiquinoline in medium of HCl and acetone up to pH 5 and 9, respectively. The products obtained
show the same composition, Sn(C9H6ON)2; however there are some differences regarding both the thermal behaviour in an oxidant atmosphere and morphology. These products
were characterised by elemental and complexometric analysis, TG and DTA curves, infrared and X-ray diffractometry. TG curves
show, above 448 K, the partial oxidation on air atmosphere of Sn(II) complexes to Sn(IV) complexes, SnO(C9H6ON)2. This behaviour does not depend only on pH in which the compounds were obtained but also on the heating rate in TG curves.
Sn(II) complexes volatilise almost completely on nitrogen atmosphere and partially on air atmosphere depending on the oxidation
degree of the compound.
batteries by changing parameters about physical property, heat generation rate and environment [ 7 ]. Therefore, it is very important to study the thermalbehavior of them. Modeling and simulation of the battery's thermalbehavior are useful for obtaining
Authors:C. Ferragina, A. La Ginestra, M. Massucci, P. Cafarelli, and R. Di Rocco
Two methods are described in order to obtain copper-2,9-dimethyl-1, 10-phenanthroline (dmp) coordination compounds intercalated
between the layers of α-Zr(HPO4)2·H2O and ψ-Zr(H2PO4)(PO4)·2H2O: the direct intercalation of Cu-dmp complex species or the formation ‘insitu’ of coordination compounds. With the first
exchanger both methods lead to similar products with X-ray diffraction patterns practically identical. They contain Cu(II–I)-dmp
complex species that confer to the solids an initially green colour slowly turning to yellow with time or temperature when
the reduction of Cu(II) to Cu(I) is complete. With λ-ZrP(H2PO4)(PO4)·2H2O, only the direct insertion is successful. TG/DTA experiments permit a better understanding of what is occurring in the materials
during the copper reduction step, in correspondance of which, a strong endothermic peak and a gain in weight can be observed.
They also show how the difference in the structure and chemical formula of the two exchangers affect the thermal behaviour
of the two series of compounds.